Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

New Accounting Pronouncements or Change in Accounting Principle [Line Items]

Schedule of Changes in Allowance for Doubtful Accounts

The following table presents the changes in the allowance for doubtful accounts (in thousands):

	Year ended December 31,
	2019		2018		2017
Balance, beginning of year	$	7,296	$	4,486	$	1,792
Add: provision for doubtful accounts	9,129		7,353		4,558
Less: write-offs, net of recoveries and other adjustments	(7,376)		(4,543)		(1,864)
Balance, end of year	$	9,049	$	7,296	$	4,486

Schedule of Changes in Contractual Allowance

The following table presents the changes in the contractual allowance (in thousands):

	Year ended December 31,
	2019		2018		2017
Balance, beginning of year	$	9,205	$	6,345	$	2,340
Add: allowance for contractual adjustments	15,518		9,095		4,664
Less: contractual adjustments	(9,290)		(6,235)		(659)
Balance, end of year	$	15,433	$	9,205	$	6,345

Disaggregated Revenue by Payor Type and Major Service

The Company disaggregates revenue from contracts with customers by payor type. The Company believes these categories aggregate the payor types by nature, amount, timing and uncertainty of its revenue streams. Disaggregated revenue by payor type and major service line for the years ended December 31, 2019 and December 31, 2018 was as follows (in thousands):

	Year Ended December 31, 2019		Year Ended December 31, 2018
Contracted third-party payors	$	101,845	$	56,949
Non-contracted third-party payors	10,770		12,447
Centers for Medicare & Medicaid	58,918		40,482
Healthcare Institutions	43,019		37,399
Total	$	214,552	$	147,277